Antiflea fibers

ABSTRACT

Melt-spun filaments having a substance incorporated therein to kill fleas and staple length fibers made therefrom are described. Carpets containing these fibers are useful for ridding households and household pets of fleas.

This invention relates to a simple and effective means for ridding households and household pets of the common flea (Ctenocephalides canis and felis).

Fleas are the Draculas of the insect world and are the leading cause of skin allergies in dogs and cats. Fleas also are often the carriers of serious diseases and parasites - like tapeworms - that can infect dogs and humans alike. Without a proper plan of attack the pet owner is certain to lose in the war against fleas. Fleas are hard to see and even harder to kill. The flea is slightly larger than 1/32 of an inch (0.08 cm) in length, is red, brown or black in color and is protected by a hard flat shell. The feet of a flea have double claws for catching hold of the pet's skin and fur in a pinching manner. Once attached to the pet, the flea has spine-like teeth that bite and cause inflammation of the pet's skin. The flea can leap 8 inches (20.3 cm) high and a distance of 12 inches (30.5 cm). One mating pair of fleas may, in their 274-day lifetime, be responsible for the creation of 250,000 fleas. Fleas spend only 10% to 20% of their life on the pet, the remainder is spent in the environment, be it in the yard or the house. Fleas can remain frozen for considerable periods of time and still thaw out and be as good as new. Once in the house, fleas become a year-around household problem. In fact, for the flea, a carpet is probably preferable to the yard. Fleas are primarily a parasite of household pets (dogs and cats). However, if all pets are removed from a household having fleas, the fleas will then attack humans.

Various chemical treatments, either of the pet or the pet's environment or both, have been recommended for the purpose of ridding the pet and its environment of the flea. The treatments include shampoos and dips for external application to the pet, medicines for internal application to the pet, and spraying and fogging for application to the pet's environment. Chemicals which have been used in conjunction with the treatments are well-known in the art and include terpenes (e.g. d-limonene), malathion, diazinon, and organophosphates. U.S. Pat. No. 4,379,168 describes pesticide compositions containing d-limonene along with surfactants or emulsifiers and water.

Such treatments, however, are only of a temporary nature. Moreover, care must be exercised in application of the chemicals to avoid irritation of the pet's skin. For example, the treatments are usually infrequent (e.g. shampoos being bi-weekly and dips being every six weeks).

Accordingly, there is a need in the art to provide a means for rescuing the homeowner and household pet from the common flea.

SUMMARY OF THE INVENTION

The present invention provides a simple, safe and effective means for ridding pets and households of the common flea. Specifically, the invention provides fibers selected from the group consisting of melt-spun filaments characterized in having an antiflea agent incorporated therein and exposed at the fiber surface in an amount sufficient to control fleas which come into contact with the fiber and staple length fibers made from such melt-spun filaments. The term "fiber", as used herein, means fibers of continuous length (filaments) or of short length (staple) and yarns consisting of such fibers.

The term "antiflea agent", as used herein, means a chemical substance which is effective for controlling (i.e. killing or repelling) the common flea. The fibers of the invention are characterized in having a low concentration of the agent available at the fiber surface for immediate use in controlling fleas and additional agent beneath the fiber surface for future use in controlling fleas. Thus, as agent is lost from the fiber surface with time for whatever reason, fresh agent migrates to the fiber surface to take its place. In effect, the antiflea agent is "time-released" from the fiber. In this manner, the concentration of the agent may be maintained at a safe level, there is no obnoxious odors associated with the agent, and the flea protection is of a relatively permanent nature. These results are not obtained if the agent, instead of being incorporated into the fibers, is merely present as a surface coating on the fibers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

Melt-spun filaments useful in practicing the invention include filaments melt-spun from polyolefins (e.g. polypropylene), nylon (e.g. nylon 66 and nylon 6) and polyesters (e.g. polyethylene terephthalate) and staple length fibers made therefrom.

The antiflea agent is preferably incorporated into the fibers during melt-spinning of the filaments by applying the agents to the filaments either prior to or along with spin finish application. When applied prior to spin finish application, the agent is preferably applied from an aqueous emulsion thereof. Spin finish containing agent may be applied to the filaments in a conventional manner, for example, by passing the filaments over a metered finish applicator where a predetermined amount of finish is applied to the filaments and the filaments converged to form a yarn. The yarn normally is then either drawn and collected or collected and drawn in a separate operation. Alternatively, the agents may be incorporated into the polymer from which the filaments are melt-spun, for example, by adding the agent to the molten polymer just prior to melt-spinning of the filaments.

A particularly preferred antiflea agent for use in practicing the present invention is d-limonen which is a terpene. Other effective terpenes are pinen, cincole, carvone, phellandrene and terpineol. d-Limonene, which is the major constituent of citrus oils, is known to be effective in controlling insects, including fleas, is inexpensive, abundant and is reported to be non-toxic to both pets and humans.

The concentration of the antiflea agent in the fiber may vary over a wide range depending on the particular agent employed and the particular intended end use application for the fibers.

The fibers of the present invention are particularly useful for making flea-free carpet. The flea-free carpet may, for example, be used in the form of wall-to-wall carpet or area rugs that protects the pet and entire household from fleas or it may be used in the form of a pad on which the pet sleeps or rests. In constructing the flea-free carpet, the fibers of the invention may be used as pile fibers or as "grin cover" fibers. Grin cover fibers cover the upper surface of the primary backing of cut pile carpet and is exposed when the pile fibers fail, for whatever reason, to completely cover the primary backing. Typically, grin cover fibers are of the same chemical composition fiber as the pile fibers and are needle punched into the primary backing. When the carpet is dyed, the grin cover fibers and pile fibers are dyed to the same shade of color.

The following example is given for the purpose of further illustrating the invention and is not intended in any way to limit the scope of the invention to the particular materials described herein. In the examples, percentages are by weight unless otherwise specified.

EXAMPLE

This example illustrates preparation of fibers of the present invention and their utility in controlling fleas.

Nylon 66 polymer of fiber-forming grade is melt-spun into 4080 denier, 68 filament carpet yarn in a conventional matter. During melt spinning, the filaments, after being quenched, are passed over a conventional metered finish applicator where the filaments are converged to form a yarn and where a sufficient amount of a solution consisting of 60% d-limonene and 40% emulsifier (Tween®20) is applied to the yarn to provide filaments having 1.8% by weight of d-limonene incorporated therein. The yarn is then passed through a conventional steam conditioning tube measuring about 1.8 meters in length where the yarn is treated with steam to facilitate subsequent collection of the yarn. The yarn is then passed over a conventional metered finish applicator where an aqueous spin finish containing a lubricant is applied to the yarn. The yarn is then passed over and around a driven feed roll and its associated separator roll with several wraps and finally collected on a bobbin. A sufficient amount of a solution consisting of 60% d-limonene and 40% emulsifier (Tween®20) is applied to the filaments after convergence and before steam conditioning to provide filaments having 1.8% d-limonene on weight of fiber (o.w.f.) incorporated therein. The as-spun yarn is then drawn to a denier of 1340, textured and tufted into cut-pile carpet.

In one experiment, a square carpet sample measuring 150 mm×150 mm is placed pile side up in a cylindrical glass container having a diameter of 175 mm, a height of 75 mm and being open at one end. Ten fleas are removed from a four-year old black female pug and placed in the container. The open end of the container is covered with a fine woven nylon fabric and the fabric secured to the container by means of rubber bands. The fabric prevents the fleas from escaping while allowing fresh air to circulate in the container. After a period of 24 hours, all of the fleas are dead.

In a second experiment, the first experiment is repeated, except in this instance the antiflea agent is omitted from the carpet sample. After a period of 24 hours, all of the fleas are still active.

The above experiments show that the fibers of the present invention provide is a simple, economical and effective means for ridding households and household pets of fleas that otherwise infest households and torment and even kill household pets.

Although the specification has been directed to using the fibers of the present invention to control fleas, it will be understood that the antiflea agent will also control other insects, for example, d-limonene will control ants and fleas. The particular insects, in addition to fleas, which can be controlled by application of the fibers of the invention will, of course, depend on the particular antiflea agent incorporated into the fibers and the concentration thereof. 

What is claimed is:
 1. A fiber selected from the group consisting of melt-spun filaments characterized in having an antiflea agent incorporated therein and exposed at the surface thereof in an amount sufficient to control fleas which come into contact therewith and staple length fibers made from said filaments.
 2. The fiber of claim 1 wherein said fiber is a nylon fiber.
 3. The fiber of claim 2 wherein said antiflea agent is a terpene.
 4. The fiber of claim 3 wherein said terpene is d-limonene.
 5. A yarn consisting essentially of fibers of claim
 4. 6. The yarn of claim 5 wherein said fibers are staple length fibers.
 7. The yarn of claim 5 wherein said fibers are melt-spun filaments.
 8. A flea-free carpet comprising a primary backing having pile fibers attached thereto characterized in that said pile fibers comprise fibers selected from the group consisting of melt-spun filaments having an antiflea agent incorporated therein and exposed at the surface thereof in an amount sufficient to control fleas which come into contact therewith and staple length fibers made from said filaments.
 9. A flea-free carpet comprising a primary backing having grin cover fibers and pile fibers attached thereto characterized in that said grin cover fibers comprise fibers selected from the group consisting of melt-spun filaments having an antiflea agent incorporated therein and exposed at the surface thereof in an amount sufficient to control fleas which come into contact therewith and staple length fibers made from said filaments.
 10. The flea-free carpet of claim 8 wherein said antiflea agent is d-limonene.
 11. The flea-free carpet of claim 9 wherein said antiflea agent d-limonene.
 12. The flea-free carpet of claim 10 wherein said pile fibers are nylon fibers.
 13. The flea-free carpet of claim 11 wherein said pile fibers and said grin cover fibers are nylon fibers. 